As an assembly employed for use in a catalytic converter, a filter, a heat exchanger or the like used for purifying the exhaust gas from an internal combustion engine or used for a chemical reaction instrument taking advantage of catalytic action, there have been known articles in which cell structures are held by and housed in metallic containers (canning) by interposing a compressive material having a cushioning property between the cell structure and the metallic container (a can body) and thereby giving a prescribed compressive contact stress to the cell structure through the compressive material.
For example, in the case where such an assembly is used as a catalytic converter for use in purifying automobile exhaust gas, a ceramic honeycomb structure, a type of cell structure, in which noble metals such as platinum, palladium, rhodium, or the like are dispersed and carried as catalytic components, is held by and housed in a metallic container (a can body) through the intermediary of a ceramic mat or the like, and is mounted in an exhaust system.
As in the above-described catalytic converter, in the case where a catalytic component is carried in the cell structure, an appropriate amount to be carried varies, depending on the masses of the cell structures. Conventionally, the masses of the cell structures are measured beforehand and the cell structures are sorted into several classes based on mass, and the amount of the carried catalytic component (the mass of the catalytic component) is adjusted so as to become the fixed value by controlling the masses after the catalytic component has been carried based on each class of the mass. However, since the masses of the cell structures have a certain variation even within the same class of the mass range, actually some variance exists in the carried amount of the catalytic component if it is examined at the individual cell structures.
The present invention has been completed, in view of the above described problems in the prior art, and the object thereof is to provide a processing method for carrying a catalytic component on each cell with an appropriate amount thereof in accordance with the mass of the cell structure, at the time when the processing for carrying a catalyst component on the cell structure is done, even if there is a variation in the mass of the cell structure.